1. Field of the Invention
The present invention generally relates to apparatus for recording and/or reproducing a video signal and, more particularly, is directed to an apparatus for recording and/or reproducing a video signal for use with a video tape recorder having a built-in camera.
2. Description of the Prior Art
As a recording apparatus for recording a still image as an electrical video signal, a so-called electronic still camera has been developed to record a still image on a magnetic disc as a video signal. With this electronic still camera, processing such as development or the like is not required, unlike a standard camera using a halide film. The electronic still camera can reproduced a picked-up still image immediately merely by connecting it to a television receiver.
However, a still image picked-up by such electronic still camera is poor in resolution as compared with a still image picked-up by a standard camera using halide film and therefore it has been proposed that an electronic still camera capable of picking up a still image of high resolution be developed. Since the magnetic disc provided as a recording medium has restrictions on its size and so on, the resolution can not be improved as desired so long as the magnetic disc is utilized.
To obviate the aforementioned problem, an electronic still camera utilizing a semiconductor memory as a recording medium has been developed, in which a video signal of a picked-up still image is converted into a digital signal and the resultant video signal is stored and recorded in the semiconductor memory, thereby obtaining a still image of high resolution. This type of electronic still camera needs a semiconductor memory of large storage capacity and the recording medium becomes very expensive, so that this electronic still camera is utilized only as a professional electronic still camera.
On the other hand, as a consumer video apparatus, a video tape recorder (VTR) is now widely available on the market and it has been suggested that an image of high resolution can be recorded by utilizing this consumer video tape recorder (VTR). In this case, however, it takes a lot of time to record and process a still image of high resolution, and as a consequence, it is impossible to record a plurality of still images which are picked-up successively.
To solve this problem, the assignee of the present application has previously proposed a record and/or reproducing apparatus in which a digital video signal of one field or frame is recorded on a pulse code modulated (PCM) audio data recording portion of a data format of a video tape recorder, such as an 8-mm video tape recorder (see Japanese Patent Application No. 2 -46816). In that case, the digital video signal of one field or one frame is recorded in the PCM audio data recording portion of several tens to several hundreds of tracks. Since the digital video signal is recorded as described above, a still image of high resolution can be recorded efficiently.
The digital video signal for one still image is recorded over a plurality of tracks as described above, so that, when a video signal of a new still image is recorded on the tape on which the video signal of the first still image is already recorded, an ending portion of the first recorded video signal must be detected and the video signal of the new still image must begin at this ending portion. If the video signal of the new still image is not positioned as described above, then the new video signal may be recorded on a track in which the video signal of the first still image is already recorded. There is then the problem that the previously-recorded signal is erased unintentionally.
If the ending portion of the first still image signal recorded over several hundreds of tracks is searched for in a normal playback mode, then it takes a large amount of time to detect this ending portion of the first still image signal.